ypbind.c revision 1.52 1 /* $NetBSD: ypbind.c,v 1.52 2004/09/07 13:20:40 jrf Exp $ */
2
3 /*
4 * Copyright (c) 1992, 1993 Theo de Raadt <deraadt (at) fsa.ca>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
17 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
20 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/cdefs.h>
30 #ifndef LINT
31 __RCSID("$NetBSD: ypbind.c,v 1.52 2004/09/07 13:20:40 jrf Exp $");
32 #endif
33
34 #include <sys/param.h>
35 #include <sys/types.h>
36 #include <sys/ioctl.h>
37 #include <sys/signal.h>
38 #include <sys/socket.h>
39 #include <sys/file.h>
40 #include <sys/uio.h>
41 #include <sys/syslog.h>
42 #include <sys/stat.h>
43 #include <fcntl.h>
44 #include <limits.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <errno.h>
48 #include <syslog.h>
49 #include <stdarg.h>
50 #include <ctype.h>
51 #include <dirent.h>
52 #include <netdb.h>
53 #include <string.h>
54 #include <err.h>
55 #include <rpc/rpc.h>
56 #include <rpc/xdr.h>
57 #include <net/if.h>
58 #include <arpa/inet.h>
59 #include <rpc/pmap_clnt.h>
60 #include <rpc/pmap_prot.h>
61 #include <rpc/pmap_rmt.h>
62 #include <unistd.h>
63 #include <util.h>
64 #include <rpcsvc/yp_prot.h>
65 #include <rpcsvc/ypclnt.h>
66 #include <ifaddrs.h>
67
68 #include "pathnames.h"
69
70 #ifndef O_SHLOCK
71 #define O_SHLOCK 0
72 #endif
73
74 #define BUFSIZE 1400
75
76 #define YPSERVERSSUFF ".ypservers"
77 #define BINDINGDIR (_PATH_VAR_YP "binding")
78
79 struct _dom_binding {
80 struct _dom_binding *dom_pnext;
81 char dom_domain[YPMAXDOMAIN + 1];
82 struct sockaddr_in dom_server_addr;
83 int dom_socket;
84 CLIENT *dom_client;
85 long dom_vers;
86 time_t dom_check_t;
87 time_t dom_ask_t;
88 int dom_lockfd;
89 int dom_alive;
90 u_int32_t dom_xid;
91 };
92
93 static char *domainname;
94
95 static struct _dom_binding *ypbindlist;
96 static int check;
97
98 typedef enum {
99 YPBIND_DIRECT, YPBIND_BROADCAST, YPBIND_SETLOCAL, YPBIND_SETALL
100 } ypbind_mode_t;
101
102 ypbind_mode_t ypbindmode;
103
104 /*
105 * If ypbindmode is YPBIND_SETLOCAL or YPBIND_SETALL, this indicates
106 * whether or not we've been "ypset". If we haven't, we behave like
107 * YPBIND_BROADCAST. If we have, we behave like YPBIND_DIRECT.
108 */
109 int been_ypset;
110
111 #ifdef DEBUG
112 static int debug;
113 #endif
114
115 static int insecure;
116 static int rpcsock, pingsock;
117 static struct rmtcallargs rmtca;
118 static struct rmtcallres rmtcr;
119 static bool_t rmtcr_outval;
120 static u_long rmtcr_port;
121 static SVCXPRT *udptransp, *tcptransp;
122
123 int _yp_invalid_domain(const char *); /* from libc */
124 int main(int, char *[]);
125
126 static void usage(void);
127 static void yp_log(int, const char *, ...)
128 __attribute__((__format__(__printf__, 2, 3)));
129 static struct _dom_binding *makebinding(const char *);
130 static int makelock(struct _dom_binding *);
131 static void removelock(struct _dom_binding *);
132 static void *ypbindproc_null_2(SVCXPRT *, void *);
133 static void *ypbindproc_domain_2(SVCXPRT *, void *);
134 static void *ypbindproc_setdom_2(SVCXPRT *, void *);
135 static void ypbindprog_2(struct svc_req *, SVCXPRT *);
136 static void checkwork(void);
137 static int ping(struct _dom_binding *);
138 static int nag_servers(struct _dom_binding *);
139 static enum clnt_stat handle_replies(void);
140 static enum clnt_stat handle_ping(void);
141 static void rpc_received(char *, struct sockaddr_in *, int);
142 static struct _dom_binding *xid2ypdb(u_int32_t);
143 static u_int32_t unique_xid(struct _dom_binding *);
144 static int broadcast(char *, int);
145 static int direct(char *, int);
146 static int direct_set(char *, int, struct _dom_binding *);
147
148 static void
149 usage(void)
150 {
151 char *opt = "";
152 #ifdef DEBUG
153 opt = " [-d]";
154 #endif
155
156 (void)fprintf(stderr,
157 "usage: %s [-broadcast] [-insecure] [-ypset] [-ypsetme] %s\n",
158 getprogname(), opt);
159 exit(1);
160 }
161
162 static void
163 yp_log(int pri, const char *fmt, ...)
164 {
165 va_list ap;
166
167 va_start(ap, fmt);
168
169 #if defined(DEBUG)
170 if (debug)
171 vfprintf(stderr, fmt, ap);
172 else
173 #endif
174 vsyslog(pri, fmt, ap);
175 va_end(ap);
176 }
177
178 static struct _dom_binding *
179 makebinding(const char *dm)
180 {
181 struct _dom_binding *ypdb;
182
183 if ((ypdb = (struct _dom_binding *)malloc(sizeof *ypdb)) == NULL) {
184 yp_log(LOG_ERR, "makebinding");
185 exit(1);
186 }
187
188 (void)memset(ypdb, 0, sizeof *ypdb);
189 (void)strlcpy(ypdb->dom_domain, dm, sizeof ypdb->dom_domain);
190 return ypdb;
191 }
192
193 static int
194 makelock(struct _dom_binding *ypdb)
195 {
196 int fd;
197 char path[MAXPATHLEN];
198
199 (void)snprintf(path, sizeof(path), "%s/%s.%ld", BINDINGDIR,
200 ypdb->dom_domain, ypdb->dom_vers);
201
202 if ((fd = open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1) {
203 (void)mkdir(BINDINGDIR, 0755);
204 if ((fd = open(path, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644)) == -1)
205 return -1;
206 }
207
208 #if O_SHLOCK == 0
209 (void)flock(fd, LOCK_SH);
210 #endif
211 return fd;
212 }
213
214 static void
215 removelock(struct _dom_binding *ypdb)
216 {
217 char path[MAXPATHLEN];
218
219 (void)snprintf(path, sizeof(path), "%s/%s.%ld",
220 BINDINGDIR, ypdb->dom_domain, ypdb->dom_vers);
221 (void)unlink(path);
222 }
223
224 static void *
225 ypbindproc_null_2(SVCXPRT *transp, void *argp)
226 {
227 static char res;
228
229 #ifdef DEBUG
230 if (debug)
231 printf("ypbindproc_null_2\n");
232 #endif
233 (void)memset(&res, 0, sizeof(res));
234 return (void *)&res;
235 }
236
237 static void *
238 ypbindproc_domain_2(SVCXPRT *transp, void *argp)
239 {
240 static struct ypbind_resp res;
241 struct _dom_binding *ypdb;
242 char *arg = *(char **) argp;
243 time_t now;
244 int count;
245
246 #ifdef DEBUG
247 if (debug)
248 printf("ypbindproc_domain_2 %s\n", arg);
249 #endif
250 if (_yp_invalid_domain(arg))
251 return NULL;
252
253 (void)memset(&res, 0, sizeof res);
254 res.ypbind_status = YPBIND_FAIL_VAL;
255
256 for (count = 0, ypdb = ypbindlist;
257 ypdb != NULL;
258 ypdb = ypdb->dom_pnext, count++) {
259 if (count > 100)
260 return NULL; /* prevent denial of service */
261 if (!strcmp(ypdb->dom_domain, arg))
262 break;
263 }
264
265 if (ypdb == NULL) {
266 ypdb = makebinding(arg);
267 ypdb->dom_vers = YPVERS;
268 ypdb->dom_alive = 0;
269 ypdb->dom_lockfd = -1;
270 removelock(ypdb);
271 ypdb->dom_xid = unique_xid(ypdb);
272 ypdb->dom_pnext = ypbindlist;
273 ypbindlist = ypdb;
274 check++;
275 #ifdef DEBUG
276 if (debug)
277 printf("unknown domain %s\n", arg);
278 #endif
279 return NULL;
280 }
281
282 if (ypdb->dom_alive == 0) {
283 #ifdef DEBUG
284 if (debug)
285 printf("dead domain %s\n", arg);
286 #endif
287 return NULL;
288 }
289
290 #ifdef HEURISTIC
291 time(&now);
292 if (now < ypdb->dom_ask_t + 5) {
293 /*
294 * Hmm. More than 2 requests in 5 seconds have indicated
295 * that my binding is possibly incorrect.
296 * Ok, do an immediate poll of the server.
297 */
298 if (ypdb->dom_check_t >= now) {
299 /* don't flood it */
300 ypdb->dom_check_t = 0;
301 check++;
302 }
303 }
304 ypdb->dom_ask_t = now;
305 #endif
306
307 res.ypbind_status = YPBIND_SUCC_VAL;
308 res.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr.s_addr =
309 ypdb->dom_server_addr.sin_addr.s_addr;
310 res.ypbind_respbody.ypbind_bindinfo.ypbind_binding_port =
311 ypdb->dom_server_addr.sin_port;
312 #ifdef DEBUG
313 if (debug)
314 printf("domain %s at %s/%d\n", ypdb->dom_domain,
315 inet_ntoa(ypdb->dom_server_addr.sin_addr),
316 ntohs(ypdb->dom_server_addr.sin_port));
317 #endif
318 return &res;
319 }
320
321 static void *
322 ypbindproc_setdom_2(SVCXPRT *transp, void *argp)
323 {
324 struct ypbind_setdom *sd = argp;
325 struct sockaddr_in *fromsin, bindsin;
326 static bool_t res;
327
328 #ifdef DEBUG
329 if (debug)
330 printf("ypbindproc_setdom_2 %s\n", inet_ntoa(bindsin.sin_addr));
331 #endif
332 (void)memset(&res, 0, sizeof(res));
333 fromsin = svc_getcaller(transp);
334
335 switch (ypbindmode) {
336 case YPBIND_SETLOCAL:
337 if (fromsin->sin_addr.s_addr != htonl(INADDR_LOOPBACK)) {
338 #ifdef DEBUG
339 if (debug)
340 printf("ypset from %s denied\n",
341 inet_ntoa(fromsin->sin_addr));
342 #endif
343 return NULL;
344 }
345 /* FALLTHROUGH */
346
347 case YPBIND_SETALL:
348 been_ypset = 1;
349 break;
350
351 case YPBIND_DIRECT:
352 case YPBIND_BROADCAST:
353 default:
354 #ifdef DEBUG
355 if (debug)
356 printf("ypset denied\n");
357 #endif
358 return NULL;
359 }
360
361 if (ntohs(fromsin->sin_port) >= IPPORT_RESERVED) {
362 #ifdef DEBUG
363 if (debug)
364 printf("ypset from unprivileged port denied\n");
365 #endif
366 return &res;
367 }
368
369 if (sd->ypsetdom_vers != YPVERS) {
370 #ifdef DEBUG
371 if (debug)
372 printf("ypset with wrong version denied\n");
373 #endif
374 return &res;
375 }
376
377 (void)memset(&bindsin, 0, sizeof bindsin);
378 bindsin.sin_family = AF_INET;
379 bindsin.sin_len = sizeof(bindsin);
380 bindsin.sin_addr = sd->ypsetdom_addr;
381 bindsin.sin_port = sd->ypsetdom_port;
382 rpc_received(sd->ypsetdom_domain, &bindsin, 1);
383
384 #ifdef DEBUG
385 if (debug)
386 printf("ypset to %s succeeded\n", inet_ntoa(bindsin.sin_addr));
387 #endif
388 res = 1;
389 return &res;
390 }
391
392 static void
393 ypbindprog_2(struct svc_req *rqstp, register SVCXPRT *transp)
394 {
395 union {
396 char ypbindproc_domain_2_arg[YPMAXDOMAIN + 1];
397 struct ypbind_setdom ypbindproc_setdom_2_arg;
398 } argument;
399 struct authunix_parms *creds;
400 char *result;
401 xdrproc_t xdr_argument, xdr_result;
402 void *(*local)(SVCXPRT *, void *);
403
404 switch (rqstp->rq_proc) {
405 case YPBINDPROC_NULL:
406 xdr_argument = xdr_void;
407 xdr_result = xdr_void;
408 local = ypbindproc_null_2;
409 break;
410
411 case YPBINDPROC_DOMAIN:
412 xdr_argument = xdr_ypdomain_wrap_string;
413 xdr_result = xdr_ypbind_resp;
414 local = ypbindproc_domain_2;
415 break;
416
417 case YPBINDPROC_SETDOM:
418 switch (rqstp->rq_cred.oa_flavor) {
419 case AUTH_UNIX:
420 creds = (struct authunix_parms *)rqstp->rq_clntcred;
421 if (creds->aup_uid != 0) {
422 svcerr_auth(transp, AUTH_BADCRED);
423 return;
424 }
425 break;
426 default:
427 svcerr_auth(transp, AUTH_TOOWEAK);
428 return;
429 }
430
431 xdr_argument = xdr_ypbind_setdom;
432 xdr_result = xdr_void;
433 local = ypbindproc_setdom_2;
434 break;
435
436 default:
437 svcerr_noproc(transp);
438 return;
439 }
440 (void)memset(&argument, 0, sizeof(argument));
441 if (!svc_getargs(transp, xdr_argument, (caddr_t)&argument)) {
442 svcerr_decode(transp);
443 return;
444 }
445 result = (*local)(transp, &argument);
446 if (result != NULL && !svc_sendreply(transp, xdr_result, result)) {
447 svcerr_systemerr(transp);
448 }
449 return;
450 }
451
452 int
453 main(int argc, char *argv[])
454 {
455 struct timeval tv;
456 fd_set fdsr;
457 int width, lockfd;
458 int evil = 0, one;
459 char pathname[MAXPATHLEN];
460 struct stat st;
461
462 yp_get_default_domain(&domainname);
463 if (domainname[0] == '\0')
464 errx(1, "Domainname not set. Aborting.");
465
466 /*
467 * Per traditional ypbind(8) semantics, if a ypservers
468 * file does not exist, we default to broadcast mode.
469 * If the file does exist, we default to direct mode.
470 * Note that we can still override direct mode by passing
471 * the -broadcast flag.
472 */
473 snprintf(pathname, sizeof(pathname), "%s/%s%s", BINDINGDIR,
474 domainname, YPSERVERSSUFF);
475 if (stat(pathname, &st) < 0) {
476 #ifdef DEBUG
477 if (debug)
478 fprintf(stderr,
479 "%s does not exist, defaulting to broadcast\n",
480 pathname);
481 #endif
482 ypbindmode = YPBIND_BROADCAST;
483 } else
484 ypbindmode = YPBIND_DIRECT;
485
486 while (--argc) {
487 ++argv;
488 if (!strcmp("-insecure", *argv))
489 insecure = 1;
490 else if (!strcmp("-ypset", *argv))
491 ypbindmode = YPBIND_SETALL;
492 else if (!strcmp("-ypsetme", *argv))
493 ypbindmode = YPBIND_SETLOCAL;
494 else if (!strcmp("-broadcast", *argv))
495 ypbindmode = YPBIND_BROADCAST;
496 #ifdef DEBUG
497 else if (!strcmp("-d", *argv))
498 debug++;
499 #endif
500 else
501 usage();
502 }
503
504 /* initialise syslog */
505 openlog("ypbind", LOG_PERROR | LOG_PID, LOG_DAEMON);
506
507 /* blow away everything in BINDINGDIR */
508
509 lockfd = open(_PATH_YPBIND_LOCK, O_CREAT|O_SHLOCK|O_RDWR|O_TRUNC, 0644);
510 if (lockfd == -1)
511 err(1, "Cannot create %s", _PATH_YPBIND_LOCK);
512
513 #if O_SHLOCK == 0
514 (void)flock(lockfd, LOCK_SH);
515 #endif
516
517 (void)pmap_unset(YPBINDPROG, YPBINDVERS);
518
519 udptransp = svcudp_create(RPC_ANYSOCK);
520 if (udptransp == NULL)
521 errx(1, "Cannot create udp service.");
522
523 if (!svc_register(udptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2,
524 IPPROTO_UDP))
525 errx(1, "Unable to register (YPBINDPROG, YPBINDVERS, udp).");
526
527 tcptransp = svctcp_create(RPC_ANYSOCK, 0, 0);
528 if (tcptransp == NULL)
529 errx(1, "Cannot create tcp service.");
530
531 if (!svc_register(tcptransp, YPBINDPROG, YPBINDVERS, ypbindprog_2,
532 IPPROTO_TCP))
533 errx(1, "Unable to register (YPBINDPROG, YPBINDVERS, tcp).");
534
535 /* XXX use SOCK_STREAM for direct queries? */
536 if ((rpcsock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1)
537 err(1, "rpc socket");
538 if ((pingsock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == -1)
539 err(1, "ping socket");
540
541 (void)fcntl(rpcsock, F_SETFL, fcntl(rpcsock, F_GETFL, 0) | FNDELAY);
542 (void)fcntl(pingsock, F_SETFL, fcntl(pingsock, F_GETFL, 0) | FNDELAY);
543
544 one = 1;
545 (void)setsockopt(rpcsock, SOL_SOCKET, SO_BROADCAST, &one, sizeof(one));
546 rmtca.prog = YPPROG;
547 rmtca.vers = YPVERS;
548 rmtca.proc = YPPROC_DOMAIN_NONACK;
549 rmtca.xdr_args = NULL; /* set at call time */
550 rmtca.args_ptr = NULL; /* set at call time */
551 rmtcr.port_ptr = &rmtcr_port;
552 rmtcr.xdr_results = xdr_bool;
553 rmtcr.results_ptr = (caddr_t)&rmtcr_outval;
554
555 if (_yp_invalid_domain(domainname))
556 errx(1, "bad domainname: %s", domainname);
557
558 /* build initial domain binding, make it "unsuccessful" */
559 ypbindlist = makebinding(domainname);
560 ypbindlist->dom_vers = YPVERS;
561 ypbindlist->dom_alive = 0;
562 ypbindlist->dom_lockfd = -1;
563 removelock(ypbindlist);
564
565 checkwork();
566
567 for (;;) {
568 width = svc_maxfd;
569 if (rpcsock > width)
570 width = rpcsock;
571 if (pingsock > width)
572 width = pingsock;
573 width++;
574 fdsr = svc_fdset;
575 FD_SET(rpcsock, &fdsr);
576 FD_SET(pingsock, &fdsr);
577 tv.tv_sec = 1;
578 tv.tv_usec = 0;
579
580 switch (select(width, &fdsr, NULL, NULL, &tv)) {
581 case 0:
582 checkwork();
583 break;
584 case -1:
585 yp_log(LOG_WARNING, "select: %m");
586 break;
587 default:
588 if (FD_ISSET(rpcsock, &fdsr))
589 handle_replies();
590 if (FD_ISSET(pingsock, &fdsr))
591 handle_ping();
592 svc_getreqset(&fdsr);
593 if (check)
594 checkwork();
595 break;
596 }
597
598 if (!evil && ypbindlist->dom_alive) {
599 evil = 1;
600 #ifdef DEBUG
601 if (!debug)
602 #endif
603 daemon(0, 0);
604 pidfile(NULL);
605 }
606 }
607 }
608
609 /*
610 * State transition is done like this:
611 *
612 * STATE EVENT ACTION NEWSTATE TIMEOUT
613 * no binding timeout broadcast no binding 5 sec
614 * no binding answer -- binding 60 sec
615 * binding timeout ping server checking 5 sec
616 * checking timeout ping server + broadcast checking 5 sec
617 * checking answer -- binding 60 sec
618 */
619 void
620 checkwork(void)
621 {
622 struct _dom_binding *ypdb;
623 time_t t;
624
625 check = 0;
626
627 time(&t);
628 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext) {
629 if (ypdb->dom_check_t < t) {
630 if (ypdb->dom_alive == 1)
631 ping(ypdb);
632 else
633 nag_servers(ypdb);
634 time(&t);
635 ypdb->dom_check_t = t + 5;
636 }
637 }
638 }
639
640 int
641 ping(struct _dom_binding *ypdb)
642 {
643 char *dom = ypdb->dom_domain;
644 struct rpc_msg msg;
645 char buf[BUFSIZE];
646 enum clnt_stat st;
647 int outlen;
648 AUTH *rpcua;
649 XDR xdr;
650
651 (void)memset(&xdr, 0, sizeof xdr);
652 (void)memset(&msg, 0, sizeof msg);
653
654 rpcua = authunix_create_default();
655 if (rpcua == NULL) {
656 #ifdef DEBUG
657 if (debug)
658 printf("cannot get unix auth\n");
659 #endif
660 return RPC_SYSTEMERROR;
661 }
662
663 msg.rm_direction = CALL;
664 msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
665 msg.rm_call.cb_prog = YPPROG;
666 msg.rm_call.cb_vers = YPVERS;
667 msg.rm_call.cb_proc = YPPROC_DOMAIN_NONACK;
668 msg.rm_call.cb_cred = rpcua->ah_cred;
669 msg.rm_call.cb_verf = rpcua->ah_verf;
670
671 msg.rm_xid = ypdb->dom_xid;
672 xdrmem_create(&xdr, buf, sizeof buf, XDR_ENCODE);
673 if (!xdr_callmsg(&xdr, &msg)) {
674 st = RPC_CANTENCODEARGS;
675 AUTH_DESTROY(rpcua);
676 return st;
677 }
678 if (!xdr_ypdomain_wrap_string(&xdr, &dom)) {
679 st = RPC_CANTENCODEARGS;
680 AUTH_DESTROY(rpcua);
681 return st;
682 }
683 outlen = (int)xdr_getpos(&xdr);
684 xdr_destroy(&xdr);
685 if (outlen < 1) {
686 st = RPC_CANTENCODEARGS;
687 AUTH_DESTROY(rpcua);
688 return st;
689 }
690 AUTH_DESTROY(rpcua);
691
692 ypdb->dom_alive = 2;
693 if (sendto(pingsock, buf, outlen, 0,
694 (struct sockaddr *)&ypdb->dom_server_addr,
695 sizeof ypdb->dom_server_addr) == -1)
696 yp_log(LOG_WARNING, "ping: sendto: %m");
697 return 0;
698
699 }
700
701 static int
702 nag_servers(struct _dom_binding *ypdb)
703 {
704 char *dom = ypdb->dom_domain;
705 struct rpc_msg msg;
706 char buf[BUFSIZE];
707 enum clnt_stat st;
708 int outlen;
709 AUTH *rpcua;
710 XDR xdr;
711
712 rmtca.xdr_args = xdr_ypdomain_wrap_string;
713 rmtca.args_ptr = (char *)&dom;
714
715 (void)memset(&xdr, 0, sizeof xdr);
716 (void)memset(&msg, 0, sizeof msg);
717
718 rpcua = authunix_create_default();
719 if (rpcua == NULL) {
720 #ifdef DEBUG
721 if (debug)
722 printf("cannot get unix auth\n");
723 #endif
724 return RPC_SYSTEMERROR;
725 }
726 msg.rm_direction = CALL;
727 msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
728 msg.rm_call.cb_prog = PMAPPROG;
729 msg.rm_call.cb_vers = PMAPVERS;
730 msg.rm_call.cb_proc = PMAPPROC_CALLIT;
731 msg.rm_call.cb_cred = rpcua->ah_cred;
732 msg.rm_call.cb_verf = rpcua->ah_verf;
733
734 msg.rm_xid = ypdb->dom_xid;
735 xdrmem_create(&xdr, buf, sizeof buf, XDR_ENCODE);
736 if (!xdr_callmsg(&xdr, &msg)) {
737 st = RPC_CANTENCODEARGS;
738 AUTH_DESTROY(rpcua);
739 return st;
740 }
741 if (!xdr_rmtcall_args(&xdr, &rmtca)) {
742 st = RPC_CANTENCODEARGS;
743 AUTH_DESTROY(rpcua);
744 return st;
745 }
746 outlen = (int)xdr_getpos(&xdr);
747 xdr_destroy(&xdr);
748 if (outlen < 1) {
749 st = RPC_CANTENCODEARGS;
750 AUTH_DESTROY(rpcua);
751 return st;
752 }
753 AUTH_DESTROY(rpcua);
754
755 if (ypdb->dom_lockfd != -1) {
756 (void)close(ypdb->dom_lockfd);
757 ypdb->dom_lockfd = -1;
758 removelock(ypdb);
759 }
760
761 if (ypdb->dom_alive == 2) {
762 /*
763 * This resolves the following situation:
764 * ypserver on other subnet was once bound,
765 * but rebooted and is now using a different port
766 */
767 struct sockaddr_in bindsin;
768
769 memset(&bindsin, 0, sizeof bindsin);
770 bindsin.sin_family = AF_INET;
771 bindsin.sin_len = sizeof(bindsin);
772 bindsin.sin_port = htons(PMAPPORT);
773 bindsin.sin_addr = ypdb->dom_server_addr.sin_addr;
774
775 if (sendto(rpcsock, buf, outlen, 0, (struct sockaddr *)&bindsin,
776 sizeof bindsin) == -1)
777 yp_log(LOG_WARNING, "broadcast: sendto: %m");
778 }
779
780 switch (ypbindmode) {
781 case YPBIND_SETALL:
782 case YPBIND_SETLOCAL:
783 if (been_ypset)
784 return direct_set(buf, outlen, ypdb);
785 /* FALLTHROUGH */
786
787 case YPBIND_BROADCAST:
788 return broadcast(buf, outlen);
789
790 case YPBIND_DIRECT:
791 return direct(buf, outlen);
792 }
793
794 return -1;
795 }
796
797 static int
798 broadcast(char *buf, int outlen)
799 {
800 struct ifaddrs *ifap, *ifa;
801 struct sockaddr_in bindsin;
802 struct in_addr in;
803
804 memset(&bindsin, 0, sizeof bindsin);
805 bindsin.sin_family = AF_INET;
806 bindsin.sin_len = sizeof(bindsin);
807 bindsin.sin_port = htons(PMAPPORT);
808
809 if (getifaddrs(&ifap) != 0) {
810 yp_log(LOG_WARNING, "broadcast: getifaddrs: %m");
811 return (-1);
812 }
813 for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
814 if (ifa->ifa_addr->sa_family != AF_INET)
815 continue;
816 if ((ifa->ifa_flags & IFF_UP) == 0)
817 continue;
818
819 switch (ifa->ifa_flags & (IFF_LOOPBACK | IFF_BROADCAST)) {
820 case IFF_BROADCAST:
821 if (!ifa->ifa_broadaddr)
822 continue;
823 if (ifa->ifa_broadaddr->sa_family != AF_INET)
824 continue;
825 in = ((struct sockaddr_in *)ifa->ifa_broadaddr)->sin_addr;
826 break;
827 case IFF_LOOPBACK:
828 in = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr;
829 break;
830 default:
831 continue;
832 }
833
834 bindsin.sin_addr = in;
835 if (sendto(rpcsock, buf, outlen, 0, (struct sockaddr *)&bindsin,
836 bindsin.sin_len) == -1)
837 yp_log(LOG_WARNING, "broadcast: sendto: %m");
838 }
839 freeifaddrs(ifap);
840 return (0);
841 }
842
843 static int
844 direct(char *buf, int outlen)
845 {
846 static FILE *df;
847 static char ypservers_path[MAXPATHLEN];
848 char line[_POSIX2_LINE_MAX];
849 char *p;
850 struct hostent *hp;
851 struct sockaddr_in bindsin;
852 int i, count = 0;
853
854 if (df)
855 rewind(df);
856 else {
857 snprintf(ypservers_path, sizeof(ypservers_path),
858 "%s/%s%s", BINDINGDIR, domainname, YPSERVERSSUFF);
859 df = fopen(ypservers_path, "r");
860 if (df == NULL) {
861 yp_log(LOG_ERR, "%s: ", ypservers_path);
862 exit(1);
863 }
864 }
865
866 memset(&bindsin, 0, sizeof bindsin);
867 bindsin.sin_family = AF_INET;
868 bindsin.sin_len = sizeof(bindsin);
869 bindsin.sin_port = htons(PMAPPORT);
870
871 while(fgets(line, sizeof(line), df) != NULL) {
872 /* skip lines that are too big */
873 p = strchr(line, '\n');
874 if (p == NULL) {
875 int c;
876
877 while ((c = getc(df)) != '\n' && c != EOF)
878 ;
879 continue;
880 }
881 *p = '\0';
882 p = line;
883 while (isspace(*p))
884 p++;
885 if (*p == '#')
886 continue;
887 hp = gethostbyname(p);
888 if (!hp) {
889 yp_log(LOG_WARNING, "%s: %s", p, hstrerror(h_errno));
890 continue;
891 }
892 /* step through all addresses in case first is unavailable */
893 for (i = 0; hp->h_addr_list[i]; i++) {
894 memmove(&bindsin.sin_addr, hp->h_addr_list[0],
895 hp->h_length);
896 if (sendto(rpcsock, buf, outlen, 0,
897 (struct sockaddr *)&bindsin, sizeof bindsin) < 0) {
898 yp_log(LOG_WARNING, "direct: sendto: %m");
899 continue;
900 } else
901 count++;
902 }
903 }
904 if (!count) {
905 yp_log(LOG_WARNING, "no contactable servers found in %s",
906 ypservers_path);
907 return -1;
908 }
909 return 0;
910 }
911
912 static int
913 direct_set(char *buf, int outlen, struct _dom_binding *ypdb)
914 {
915 struct sockaddr_in bindsin;
916 char path[MAXPATHLEN];
917 struct iovec iov[2];
918 struct ypbind_resp ybr;
919 SVCXPRT dummy_svc;
920 int fd, bytes;
921
922 /*
923 * Gack, we lose if binding file went away. We reset
924 * "been_set" if this happens, otherwise we'll never
925 * bind again.
926 */
927 snprintf(path, sizeof(path), "%s/%s.%ld", BINDINGDIR,
928 ypdb->dom_domain, ypdb->dom_vers);
929
930 if ((fd = open(path, O_SHLOCK|O_RDONLY, 0644)) == -1) {
931 yp_log(LOG_WARNING, "%s: %m", path);
932 been_ypset = 0;
933 return -1;
934 }
935
936 #if O_SHLOCK == 0
937 (void)flock(fd, LOCK_SH);
938 #endif
939
940 /* Read the binding file... */
941 iov[0].iov_base = (caddr_t)&(dummy_svc.xp_port);
942 iov[0].iov_len = sizeof(dummy_svc.xp_port);
943 iov[1].iov_base = (caddr_t)&ybr;
944 iov[1].iov_len = sizeof(ybr);
945 bytes = readv(fd, iov, 2);
946 (void)close(fd);
947 if (bytes != (iov[0].iov_len + iov[1].iov_len)) {
948 /* Binding file corrupt? */
949 yp_log(LOG_WARNING, "%s: %m", path);
950 been_ypset = 0;
951 return -1;
952 }
953
954 bindsin.sin_addr =
955 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr;
956
957 if (sendto(rpcsock, buf, outlen, 0, (struct sockaddr *)&bindsin,
958 sizeof(bindsin)) < 0) {
959 yp_log(LOG_WARNING, "direct_set: sendto: %m");
960 return -1;
961 }
962
963 return 0;
964 }
965
966 static enum clnt_stat
967 handle_replies(void)
968 {
969 char buf[BUFSIZE];
970 int fromlen, inlen;
971 struct _dom_binding *ypdb;
972 struct sockaddr_in raddr;
973 struct rpc_msg msg;
974 XDR xdr;
975
976 recv_again:
977 (void)memset(&xdr, 0, sizeof(xdr));
978 (void)memset(&msg, 0, sizeof(msg));
979 msg.acpted_rply.ar_verf = _null_auth;
980 msg.acpted_rply.ar_results.where = (caddr_t)&rmtcr;
981 msg.acpted_rply.ar_results.proc = xdr_rmtcallres;
982
983 try_again:
984 fromlen = sizeof(struct sockaddr);
985 inlen = recvfrom(rpcsock, buf, sizeof buf, 0,
986 (struct sockaddr *)&raddr, &fromlen);
987 if (inlen < 0) {
988 if (errno == EINTR)
989 goto try_again;
990 return RPC_CANTRECV;
991 }
992 if (inlen < sizeof(u_int32_t))
993 goto recv_again;
994
995 /*
996 * see if reply transaction id matches sent id.
997 * If so, decode the results.
998 */
999 xdrmem_create(&xdr, buf, (u_int)inlen, XDR_DECODE);
1000 if (xdr_replymsg(&xdr, &msg)) {
1001 if ((msg.rm_reply.rp_stat == MSG_ACCEPTED) &&
1002 (msg.acpted_rply.ar_stat == SUCCESS)) {
1003 raddr.sin_port = htons((u_short)rmtcr_port);
1004 ypdb = xid2ypdb(msg.rm_xid);
1005 if (ypdb != NULL)
1006 rpc_received(ypdb->dom_domain, &raddr, 0);
1007 }
1008 }
1009 xdr.x_op = XDR_FREE;
1010 msg.acpted_rply.ar_results.proc = xdr_void;
1011 xdr_destroy(&xdr);
1012
1013 return RPC_SUCCESS;
1014 }
1015
1016 static enum clnt_stat
1017 handle_ping(void)
1018 {
1019 char buf[BUFSIZE];
1020 int fromlen, inlen;
1021 struct _dom_binding *ypdb;
1022 struct sockaddr_in raddr;
1023 struct rpc_msg msg;
1024 XDR xdr;
1025 bool_t res;
1026
1027 recv_again:
1028 (void)memset(&xdr, 0, sizeof(xdr));
1029 (void)memset(&msg, 0, sizeof(msg));
1030 msg.acpted_rply.ar_verf = _null_auth;
1031 msg.acpted_rply.ar_results.where = (caddr_t)&res;
1032 msg.acpted_rply.ar_results.proc = xdr_bool;
1033
1034 try_again:
1035 fromlen = sizeof (struct sockaddr);
1036 inlen = recvfrom(pingsock, buf, sizeof buf, 0,
1037 (struct sockaddr *)&raddr, &fromlen);
1038 if (inlen < 0) {
1039 if (errno == EINTR)
1040 goto try_again;
1041 return RPC_CANTRECV;
1042 }
1043 if (inlen < sizeof(u_int32_t))
1044 goto recv_again;
1045
1046 /*
1047 * see if reply transaction id matches sent id.
1048 * If so, decode the results.
1049 */
1050 xdrmem_create(&xdr, buf, (u_int)inlen, XDR_DECODE);
1051 if (xdr_replymsg(&xdr, &msg)) {
1052 if ((msg.rm_reply.rp_stat == MSG_ACCEPTED) &&
1053 (msg.acpted_rply.ar_stat == SUCCESS)) {
1054 ypdb = xid2ypdb(msg.rm_xid);
1055 if (ypdb != NULL)
1056 rpc_received(ypdb->dom_domain, &raddr, 0);
1057 }
1058 }
1059 xdr.x_op = XDR_FREE;
1060 msg.acpted_rply.ar_results.proc = xdr_void;
1061 xdr_destroy(&xdr);
1062
1063 return RPC_SUCCESS;
1064 }
1065
1066 /*
1067 * LOOPBACK IS MORE IMPORTANT: PUT IN HACK
1068 */
1069 void
1070 rpc_received(char *dom, struct sockaddr_in *raddrp, int force)
1071 {
1072 struct _dom_binding *ypdb;
1073 struct iovec iov[2];
1074 struct ypbind_resp ybr;
1075 int fd;
1076
1077 #ifdef DEBUG
1078 if (debug)
1079 printf("returned from %s about %s\n",
1080 inet_ntoa(raddrp->sin_addr), dom);
1081 #endif
1082
1083 if (dom == NULL)
1084 return;
1085
1086 if (_yp_invalid_domain(dom))
1087 return;
1088
1089 /* don't support insecure servers by default */
1090 if (!insecure && ntohs(raddrp->sin_port) >= IPPORT_RESERVED)
1091 return;
1092
1093 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext)
1094 if (!strcmp(ypdb->dom_domain, dom))
1095 break;
1096
1097 if (ypdb == NULL) {
1098 if (force == 0)
1099 return;
1100 ypdb = makebinding(dom);
1101 ypdb->dom_lockfd = -1;
1102 ypdb->dom_pnext = ypbindlist;
1103 ypbindlist = ypdb;
1104 }
1105
1106 /* soft update, alive */
1107 if (ypdb->dom_alive == 1 && force == 0) {
1108 if (!memcmp(&ypdb->dom_server_addr, raddrp,
1109 sizeof ypdb->dom_server_addr)) {
1110 ypdb->dom_alive = 1;
1111 /* recheck binding in 60 sec */
1112 ypdb->dom_check_t = time(NULL) + 60;
1113 }
1114 return;
1115 }
1116
1117 (void)memcpy(&ypdb->dom_server_addr, raddrp,
1118 sizeof ypdb->dom_server_addr);
1119 /* recheck binding in 60 seconds */
1120 ypdb->dom_check_t = time(NULL) + 60;
1121 ypdb->dom_vers = YPVERS;
1122 ypdb->dom_alive = 1;
1123
1124 if (ypdb->dom_lockfd != -1)
1125 (void)close(ypdb->dom_lockfd);
1126
1127 if ((fd = makelock(ypdb)) == -1)
1128 return;
1129
1130 /*
1131 * ok, if BINDINGDIR exists, and we can create the binding file,
1132 * then write to it..
1133 */
1134 ypdb->dom_lockfd = fd;
1135
1136 iov[0].iov_base = (caddr_t)&(udptransp->xp_port);
1137 iov[0].iov_len = sizeof udptransp->xp_port;
1138 iov[1].iov_base = (caddr_t)&ybr;
1139 iov[1].iov_len = sizeof ybr;
1140
1141 (void)memset(&ybr, 0, sizeof ybr);
1142 ybr.ypbind_status = YPBIND_SUCC_VAL;
1143 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_addr =
1144 raddrp->sin_addr;
1145 ybr.ypbind_respbody.ypbind_bindinfo.ypbind_binding_port =
1146 raddrp->sin_port;
1147
1148 if (writev(ypdb->dom_lockfd, iov, 2) !=
1149 iov[0].iov_len + iov[1].iov_len) {
1150 yp_log(LOG_WARNING, "writev: %m");
1151 (void)close(ypdb->dom_lockfd);
1152 removelock(ypdb);
1153 ypdb->dom_lockfd = -1;
1154 }
1155 }
1156
1157 static struct _dom_binding *
1158 xid2ypdb(u_int32_t xid)
1159 {
1160 struct _dom_binding *ypdb;
1161
1162 for (ypdb = ypbindlist; ypdb; ypdb = ypdb->dom_pnext)
1163 if (ypdb->dom_xid == xid)
1164 break;
1165 return (ypdb);
1166 }
1167
1168 static u_int32_t
1169 unique_xid(struct _dom_binding *ypdb)
1170 {
1171 u_int32_t tmp_xid;
1172
1173 tmp_xid = (u_int32_t)(((u_long)ypdb) & 0xffffffff);
1174 while (xid2ypdb(tmp_xid) != NULL)
1175 tmp_xid++;
1176
1177 return tmp_xid;
1178 }
1179